There's a heterochromatic K-Pop sensation joining Marvel Snap! A character with game-centric pedigree, Luna Snow first appeared as a video game character in 2018 in Marvel Future Fight, is a key part in the upcoming game Marvel Rivals, and now she's making her Marvel Snap debut. She's part of a long line of 3-Cost energy accelerators, but she's got an interesting twist. We'll go through the best ways to make use of Luna Snow and her Ice Cube.
Strategies

The deck-building task Luna Snow presents is to find a way to benefit from her extra energy, while not allowing your opponent to do so. There are two basic ways to go about this. First, just build your deck in a way that it takes advantage of that energy efficiently enough that your opponent can't keep up. Second, take advantage of the Ice Cube in some way. This means either destroy their Ice Cube as soon as possible to make the extra energy one-sided or find a way to ensure that it is a space hindrance by playing ways to clog your opponent. Using the Cube to clog will be a bit tricky since it will be destroyed if your opponent’s location gets filled, but you can prevent that with cards like Armor and Red Guardian. Simply having to play around the cube and its space issues will prove tricky for your opponent at times and can provide some soft disruption to their strategy.
Intriguing Synergies
Any deck that was thirsty enough for energy acceleration like Psylocke, Hope Summers, or Electro before can make use of Luna Snow. However, here are a few cards that have additional synergy with Luna Snow because of how she generates that energy.
Red Guardian is at the top of this list because it's a card that you might want in your deck anyway that can shut off your opponent’s Ice Cube if you feel it's necessary.
I think Polaris has some real potential in a format with Luna Snow. You can move your opponent's Ice Cube around in ways that inconvenience them and you can get some power for cards like Kraven and Scream in the process.
Assuming your opponent either doesn't care to or isn't able to destroy their Ice Cube, you can afflict it. Also of special note is that Ajax plus Hazmat costs 7 Energy, the exact amount Luna Snow will help you reach on turn 6. I'm skeptical if Luna Snow will be a benefit to the High Evolutionary package, but because she give you additional energy it's worth a try.
I truly believe the Second Dinner designers sit around trying to dream up ways to incrementally make Elektra more useful. Cards like Hydra Bob and Fenris Wolf didn't quite move the needle and I don't expect Elektra to get there by gaining a new role as an Ice Cube smasher, but I'm going to take her for a spin like I always do.
6-Cost Cards
The drawback of 6-Cost cards is that they need to be impactful enough on their own to be worth playing a single card on the final turn. Using Hope Summers to play a 6-Cost plus a 1-Cost has proven powerful in the past and Luna Snow is likely to be useful in similar ways. Alioth is especially powerful when it can be played alongside even a small card in another lane, and Magneto, since he already affects multiple lanes, is a good candidate too. For example, you can play 1-Cost cards like Kitty Pryde, Hydra Bob, Echo, Elektra, or one of Kate Bishop's arrows, alongside a 6-Cost card.
5-Cost Cards
Like Electro, playing Luna Snow on turn 3 will allow you to start playing 5-Cost cards a turn early. There are several 5-Cost cards that become especially powerful if they can be played early with Professor X and Vision at the top of the list. As above, having 7 energy in the last turn allows you to play combinations of cards you wouldn't otherwise be able to and there are some great 2-Cost + 5-Cost combos like Hazmat/Ajax, Dazzler/Gilgamesh, Spider-Woman/Grandmaster, and Aero/Scream.
Variants
Decks
5+2=7
Snow Shovel
Snowboarding
Igloo
LS Good Cards
Snow Jump
Final Thoughts

Luna Snow has a lot of potential to be a solid card because she comes with a solid 5-Power as a 3-Cost card and she provides one of the more powerful effects in the game, energy acceleration. The primary question about her is if her unique mechanics will be powerful enough to supplant cards like Hope Summers and Electro while competing with new, efficient energy cheats like Zabu and Wiccan who have particular synergy with 4-Costs, something Luna doesn't especially have. Her potential with Scream and Ajax/Hazmat affliction decks is enough to recommend her. Bear in mind, there are some exceptionally powerful and exciting cards this month like Doom 2099, Rocket & Groot, and Peni Parker so there will be some difficult resource decisions for Snap players this December. Luna Snow's spotlight companions X-23 and Lady Deathstrike are stronger than the returning cards later this month; it's a really strong month for new cards but particularly weak for returning cards. X-23 especially is an essential card for certain strategies, though I suspect most people who want her already have her. Get Luna Snow if you are a deck tinkerer or have enough resources saved up.